Prior to the present invention, in the railway industry, rear draft stops and bolster spacer plates have been used for a number of years. See, for example, Pages 568 and 570 of the 1970 edition of "Car and Locomotive Cyclopedia"published by Simmons-Boardman Publishing Corporation. Reference to these pages being incorporated herein by reference thereto.
These prior art draft gear stops and bolster spacer plates have been manufactured from as many as nine individual components which requires a considerable amount of welding. Obviously, such welding is expensive and can even induce premature failure of such gear draft stop and bolster spacer plate. Such failure can result, for example, from stress cracks on excessive porosity being present in the weld metal.
It is also known in the prior art, to produce the rear draft stop and bolster spacer plate members from two substantially identical pieces. In this case, the two pieces are welded together adjacent the mating surfaces to form the final rear draft stop and bolster spacer plate apparatus.
In either of the cases discussed above, welding jigs are required to maintain necessary tolerances during the fabrication process. This practice obviously adds significantly to the manufacturing cost as well as the installation cost.
As shown in the above identified reference, the rear draft stop and bolster spacer plate member can be mounted within a hollow center sill of a railway car by any number of means, such as, bolting, riveting or welding.
Further, the prior art rear draft stop and bolster spacer plate equipment discussed above is relatively heavy thereby increasing the weight of the car and the difficulty in handling the component parts.
From the above discussion, it can be seen that a need exists in the railroad industry for an improved combination rear draft stop and bolster spacer plate apparatus.